So This Is Weird—Japanese Navy Sailors Bathe in Seawater

Japan’s bath-loving culture goes to sea

Japanese love to bathe. A large majority takes a bath every evening. Lots of people are willing to travel just for a chance to...

Japanese love to bathe. A large majority takes a bath every evening. Lots of people are willing to travel just for a chance to bathe in one of Japan’s many hot springs. But what about all those thousands of poor souls aboard Japan’s warships, where water is at a premium?

The answer—seawater.

Aboard ships at sea, fresh water is a precious commodity. In many navies, including America’s, multistage flash distillation or reverse osmosis desalinates saltwater for drinking, washing and filling the ship’s boilers or reactors. Desalination is a fuel-guzzler, but without it ships would have to carry all the water they need for a voyage.

So most warships impose strict water-use regimes including the “navy shower”—a short rinse, after which a bather turns off the water and lathers up then turns the water back on to rinse. Showering this way uses a tiny percentage of the water consumed by a Westerners’ typical 10-minute morning shower.

For most Japanese, a two-minute shower and no bath just wouldn’t do. So the Japanese navy had to innovate.

To conserve water on the Imperial Japanese Navy battleship Yamato, the largest battlewagon ever built, bathing was limited by rank. Commissioned officers could use the tub daily, but the lowest-ranking sailors were limited to twice-a-week dips.

To bathe, sailors needed three coin-like bath tokens worth 10 yen each plus an antiseptic paper wipe for their genitals. One bath ticket could fill a small basin, so the sailors had to wash their whole body and groom with just three bowls of water totaling four liters. They were also free to bathe in one of two hot baths — one full of seawater, the other with freshwater … when available.

Yamato didn’t always have the freshwater in reserve, so the ship’s watch looked out for passing squalls. Spotting one on the horizon, they would call out over the main circuit for free personnel. Sailors would swarm up onto the deck to catch as much water as they could in buckets and oil cans so they could bathe without using up the ship’s supplies.

Shirane-class destroyer Kurama. Japanese navy photo

Nobody waits for squalls any more. Desalination has eased the water limits, as has shower-based plumbing. But Japanese sailors still need their baths. In port, the ship has an abundance of supplies and the sailors can enjoy regular freshwater baths. But when underway, the water rules come into effect. The ship takes on seawater and heats it up for bathing.

Sailors enter the bathroom naked and rinse themselves in a brief freshwater shower. When the water stops, they scrub, shave, shampoo and rinse. A classic navy shower. Then they step into the bath.

The saltwater has a warming effect. Sailors also report feeling a difference between Pacific and Atlantic water—the Pacific water is easier on the skin. Warmed up, the sailors hop out and shower off the salt.

The Japanese system lets sailors get their beloved bath without the ship expending a lot of extra energy on desalination, but it is less efficient than the shower-only system in the U.S. Navy. Tokyo believes morale is worth the cost.